Underground wire line core barrel apparatus



Aug. 10, 1965 A. BRAUN UNDERGROUND WIRE LINE CORE BARREL APPARATUS 3 Sheets-Sheet 1 Original Filed July 24, 1959 ME I INVENTOR. 15mm 120 4. 32.4041 my 0N AN t M 0 h v/// //////4W//////////// f Aug. 10, 1965 A. BRAUN UNDERGROUND WIRE LINE CORE BARREL APPARATUS Original Filed July 24, 1959 5 Sheets-Sheet 2 m N 4/ %/////////////v/ 3. F a N mmN rm INVENTOR 5040420 A. 3240 lrraawer:

Aug. 10, 1965 L. A. BRAUN UNDERGROUND WIRE LINE CORE BARREL APPARATUS 3 Sheets-Sheet 5 Original Filed July 24, 1959 h mHF h United States Patent 3,199,967 UNDERGROUND WIRE LENE CORE BARREL APPARATUS Leonard A. Braun, St. Paul, Minn, assignor to E. 5. Longyear Company, Minneapoiis, Minn, a corporation of Delaware Original application July 24, 1959, Ser. No. 829,429, new latent No. 3,129,283, dated Feb. 4, 1964. Divided and this application Oct. 23, 1963, 'Ser. No. 318,265

3 Claims. (Cl. 294-86.29)

The present application is a restriction or division of my corresponding application, Serial No. 829,429, fiied July 24, 1959, now Patent No. 3,120,283.

This invention relates to the art of deep core drilling in formations where the drilling direction is other than a downward direction and to new and novel improvements in apparatus for so doing. More particularly, this invention relates to new and novel improvements in wire line core drilling apparatus of the nature that is fluidly propellable to the bit end of the drill stem irrespective of the drilling direction, said apparatus including a core barrel inner tube assembly for receiving and retaining a .core, and a new and improved wire line overshot assembly for retracting said core barrel assembly from the bit end of the drill stem.

This invention has been made in order to provide wire line core barrel equipment for overcoming problems of the nature set forth hereinafter which are encountered in using core barrel equipment of the prior art. One of the problems encountered in using the Wire line core barrel equipment of the prior art is that if an outer diameter of the core barrel inner tube assembly is sufliciently large in order to form a fluid seal with the drill stem so that said assembly maybe readily fluidly propelled to the bit end of the drill stem and the drilling direction is at an angle below the horizontal, the retraction of the core barrel by wire line equipment including an overshot assembly is a relatively slow process since the assembly in being retracted would force most of the fluid intermediate said assembly and the outer end of the drill stem outwardly through the outer end of said stern. Otherwise if the assembly were rapidly retracted, the wire line would break or else a very heavy wire line would have to be provided and a large amount of power would have to be expended in rapidly retracting the overshot assembly and the core barrel inner tube assembly. In the event that the drilling direction were in a near horizontal or an upward direction, the aforementioned fluid would not have to be pulled out of the drill stem as the assemblies were retracted but rather there is present the problem of disposing of the fluid that would drain from the drill stem as the aforementioned assemblies are retracted. If the distance between the outer ends and the bit end is large, then likewise the quanti-tyof fluid to be disposed of would be large.

Further, using the wire line core barrel equipment of the prior art necessitated that a smaller diameter of core be taken than that by using the core bar-rel inner tube assembly of this invention even thought a drill stem of the same internal diameter were used in both cases. That is in the prior art equipment, the outer diameter of the core receiving tube had to be of suihciently reduced diameter so that it would pass a hanger coupling that is pro- .vided to retain the core barrel inner tube assembly adjacent to but out 0i contact with the bit. Since the core barrel inner tube assembly of the prior art is held out of contact with the bit, a fluid channel is provided between the outer peripheral surface of the inner tube assembly and the inner peripheral surface of the drill stern.

Using apparatus of this invention does away with the necessity of using a hanger coupling and still provides ddflflfi? Patented Aug. it), 1965 apparatus for centering the core barrel inner tube assembly in the drill stern and at the same time makes provision to allOW fluid to pass from the annular space between the inner peripheral wall of the drill stem and the outer peripheral wall of the core barrel inner tube assembly and thence to pass radially inwardly through the aperture of the annular bit. That is, by using apparatus of this invention wire line core barrel equipment is readily usable for exploratory drilling from underground locations such as, for example, mines, for drilling in a direction that is horizontal, upwardly (including a drilling direction that is directly overhead), or downwardly, and still be able to provide core barrel inner tube assembly setting structure wherein there can be obtained a larger diameter core than with equipment of the prior art that includes the same diameter drill stern having a core receiving tube of the same wall thickness and without having to retract the core barrel apparatus from the bit end of the drill stem at a relatively low rate of speed and/ or having to make provision for the disposal of a major portion of the drilling fluid located in the drill stem between the outer edge of said drill stern and the core barrel equipment in the bit end of the drill stem.

This invention also relates to and forms improvements in the inventions covered by US. patent applications, Ser. No. 761,889, filed September 18, 1958, now Patent No. 3,120,282, and Ser. No. 657,001, filed May 13, 1957, now abandoned, and US. Patent No. 2,829,868, issued April 8, 1958, which are incorporated herein by reference.

The principal object of this invention is to provide a new and improved wire line overshot assembly that may be readily fluidly propelled to the bit end of the drill stem regardless of the drilling direction and that readily permits fluid to bypass the assembly when said assembly is being retracted in the drill stem.

Other and further objects are those inherent in the invention herein illustrated, described, and claimed and will be apparent as the description proceeds.

To the accomplishment of the foregoing and related ends, this invention then comprises the features hereinafter fully described and particularly pointed out in the claims, the following description setting forth in detail certain illustrative embodiments of the invention, these being indicative, however, of but a few of the various ways in which the invention may be employed.

The invention is illustrated in the drawings in which the corresponding numerals refer to the same parts and in which:

FIGURE 1 is a vertical elevational View of the hydraulic mechanism including fluid connections, the core barrel inner tube assembly and the drill stem used for core drilling in other than a downward direction, said drill stem being broken away to illustrate the. core barrel inner tube assembly in a latched position for receiving core;

FIGURE 2 is an elevational view of the hydraulic mechanism including fluid connections, the core barrel inner tube assembly and the drill stem used for core drill ing in other than a downward direction, the drill stern being shown in section to illustrate the overshot assembly of this invention being fluidly propelled to the bit end of the drill stem for retracting a core barrel inner tube assembly;

FIGURE 3 is a longitud-inalsection of the core barrel overshot assembly of this invention, said overshot assembly as illustrated being fluidly propelled towards the bit end of the drill stem;

FIGURE 4 is a longitudinal section of the overshot assembly shown in FIGURE 3, said view illustrating the retract position of the overshot assembly as said assembly retracts a core barrel inner tube assembly from the bit end of the drill stem.

Referring now to the drawings and in particular to FIGURES 1 and 2, there is illustrated a hollow drill stem 1% which is commonly made up of sections of pipe coupled together and having an annular bit mounted on the inner end thereof and being fluidly connected to a hydraulic pump 25 at the outer end, said drill stem being used to take a core from an earth formation 16. As may be noted in FIGURE 1, the longitudinal axis of the drill stern extends in a horizontal direction such that a core sample may be drilled from an earth formation in other than a downward direction. As will subsequentially appear, the apparatus of this invention is particularly useful when the wire line core barrel equipment is to be used for recovering core samples where the direction of drilling is other than that wherein a core barrel inner tube assembly will fall to the bit end of the drill stem and where said core barrel assembly is to be retracted at a relatively high rate from the bit end of the drill stem by use of a wire line overshot assembly that is fluidly propelled to the bit end and still permit fluid'to by-pass the assemblies as they are retracted through the drill stem.

A chuck 17 is mounted on the outer end portion of the drill stem for rotating said stem. 'The chuck is driven in a conventional manner by power means (not shown),

said means not forming a part of this invention and therefore will not be further described.

In order that the core barrel inner tube assembly may be fluidly propelled to the bit end of the drill stem, a

water swivel, appropriate fluid lines, and valves are pro- 3 vided for fluidly connecting the hydraulic pump to the drill stem, said pump being mounted on a horizontal base 29.

the male threaded portion 21 of the swivel being attached to the outer end of the drill stem. The water swivel is of conventional construction and therefore will not be further described. It is to be understood that even though the member 20 is referred to as a water swivel the fluid used in the system described may be a liquid such as Water or specially prepared aqueous or other liquid sus The water swivel enclosed by the bracket 20 is theradedly connected to the outer end of the drill stem 10,

exhaust line 28 may be fluidly connected to the fluid pressure system. The exhaust line 28 extends from the T-joint to a sump, there being an exhaust valve 26 located in said line so that the drill stem may be selectively drained into the sump. A pressure control valve 27' is located in the pipe or pressure line 24 between the T-joint A and the pump 25.

If desired a special valving such as a plug valve (not shown) may be provided in the drill stem 2. suflicient distance inwardly from the water swivel whereby the 3 core barrel inner tube assembly 30 and the overshot assembly 125 may be retained in the drill stem intermediate said special valving and the water swivel so that the core barrel inner tube assembly and the overshot assembly may be inserted or taken out of the drill stem without the loss of a substantial quantity of fluid from the interior i of the drill stem even though the drilling directionis in an upward direction. r a a A core barrel outer tube assembly 12 is attached to a pipe section of the drill stem for receiving and retaining a core barrel inner tube assembly generally designated 31). The structure of the. core barrel outer tube assembly 12 and the inner tube assembly 30 do not, alone, form a part of this invention and will therefore not be described in further detail.

The apparatus of my invention for receiving the core having been described, I will now set forth my new and improved overshot assembly 125 and the apparatus used therewith for retracting the core barrel inner'tube assembly 30 from the bit end of the drill stem, with particular reference to FIGS. 3 and 4. The aforementioned apparatus includes a drill stem casing head, generally desig nated 110, which is attached to the head end18 of said drill stem after anovershot assembly has been inserted in the'head end of the drill stem. The aforementioned drill stem casing head is used to form a fluid connection between the pipe 22 and the head end of the drill'stem and also to permit a Wire line to be drawn therethrough.

The drill stem casing head includes a head coupling 111 having male threads at one end thereof which are threaded into the head end of the drill stem and having a transverse, aperture 111A .formed in the intermediate circumferential portion into which one end of the fluid swivel 112 is threaded; The opposite end of the fluid swivel is fluidly connected to the pipe 22.

On the outer circumferential surface ofthe head coupling 111 adjacent the outer end thereof, two pairs of spaced plate 113 are located diametricallyacross from one another. A latch 114 having a hooked end 114A is pivotally mounted between each pair of plates by the pivot pin 114B. The latched position of the latches 114 are shown in solid line in FIGURE 2 ,While the unlatched position is shown in dotted lines. V

A stufling box 115, which has a cylindrical recessed portion 115A for mounting the gland 121 'is inserted in the open end of the head coupling and is secured thereon by rotating the hook end of the latches over the outer peripheral flange 1153 of the stuffing box. A pair of spaced O-ring 116, 1 17 are positioned in grooves formed in the outer peripheral portion of the stutfing box, that is inserted into the drill stem.

The gland 121 is secured to the stufling box by four spaced stud bolts 119 (only two shown) which are inserted in appropriate apertures formed in the flange portion 121A of said gland, and screwed into threaded apertures located in the stuffing box 115. Nuts 120 are threaded on the opposite end of the stud bolts to secure the gland'in position. A central opening 121C, 115C extends through the gland and stufiing box respectively so that the Wire line 122 maybe inserted therethrough. If desired, the gland and stufling box may be formed from split sections to facilitate the insertion of the Wire line into the central openings.

Although a specific drill stem casing head structure has been set forth, it is to be understood that this is not to constitute a limitation on the invention since other structural members may be used to perform the'same functions a the drill stem casing herein described.

To retract the core barrel inner tube assembly 31) from the bit end of the drill stem without having to withdraw the fluid in the drill stemv out of the head end thereof, my new and improved overshot'assernbly, generally designated 125 has been invented. The overshot assembly may be simply dropped down on the end of the wire line if the drilling direction is in a vertical direction or may be fluidly propelled to the bit end of .the drill stem irrespective of whether the drilling direction is other than a downward direction or a near vertical direction.

The overshot assembly 125 is generally cylindrical in shape and is made up of a main body 123 and valving portion 124. The main body 123 includes a generally cylindrical overshot body 129 that has an elongated rectangular slot 128 milled in the inner central portion thereof to form two spaced overshot body segments 129A. The transverse cross section of each of the segments is of a similar shape but the segments are positioned relative to each other segment. The longitudinal length of the slot 128 extends outwardly to the line 129B. A pair of pulling dogs 126 having jaws 127 which are shaped to grasp a spear head 43 therebetween are provided, The pulling dogs 126 are disposed in face-to-face relationship in the elongated slot 128 and are pivotally e9 mounted on the pin 130 which extends through the overshot body segments to be secured therein and through the overlapping hub portions 131 of the pulley dogs. A coil compression spring 132, which is seated upon pins 133 (there being one pin welded in the outer end of each of the pulley dogs), normally urges the outer ends of the pulley dogs apart, and thus urges the jaws together in a grasping position while permitting expansion of the dogs to slide over the top of the spear point when the overshot body has been fluidly propelled to the bit end of the drill stem.

The frusto-conical shoulder 135 formed on the lower end of the overshot body aids in centering the overshot assembly over the spear point. When the spear point is retained between the jaws 127 the shoulder 135 is within close proximity of the outer end of the latch release tube and thus imparts stability to the entire assembly 30 in respect to assembly 125 as said assemblies 30', 125 are retracted through the drill stem.

The overshot body has an end 129C of reduced diameter that is secured in the inner end of the generally tubular shaped jaw element 137 by a pin 140. The jaw element has an outer end of a reduced internal diameter to form an annular shoulder 137A for slidably 'retaining the enlarged cylindrical end 141A of the spindle 141 in the opening 138 that is enclosed by the jaw element. The port 139 is formed in the jaw element to open into the opening 138 adjacent the outer end of the latch body while a second port 136 is formed in the jaw element to open into the opening 138 adjacent the shoulder 137A.

The valving portion includes a coupling element 143 and a spindle 141 having the aforementioned enlarged diametric portion 141A that forms a close fit with the opening 138, an intermediate portion 14118 of a diameter that forms a close fit with the inner peripheral wall of the annular shoulder 137A and a threaded end 141C that is threaded in coupling element 143. The coupling element 143 is generally tubular shaped and is closed at its outer end by'the cap portion 143A that has an aperture 144 formed therein that serves as an attachment for wire line or cable 122 which may be passed through the cap portion and knotted or otherwise fastened.

Mounted on the threaded end 141C of the spindle are an adjustment nut 151, a thrust washer 152, an axially compressible and radially expansible resilient collar 153, and a second thrust washer 154. The second thrust Washer is mounted on the threaded end to abut against the shoulder 141D formed at the juncture of the intermediate portion 14113 with the threaded end portion 141C while the resilient collar is positioned in abutting engagement with the first thrust washer 152 on one side and the second thrust washer on the opposite side. The adjustment nut 151 is then threaded onto the threaded end port-ion to adjustably compress the resilient collar so that it forms a close fit with the inner peripheral wall of the drill stem, said adjustment nut being in abutting engagement with the coupling element on one side and the thrust washer on the opposite side.

Formed in the intermediate portion of the jaw element is a cross bore fluid port 148. An axially extending opening 147 drilled in the spindle extends from the outer end thereof to open into the port 148. A plurality of transverse ports 146 are formed in the coupling element outwardly from the spindle to open into the opening 149 which is enclosed by said coupling element and the spindle.-

The outer diameters of the coupling element 143, the jaw element 137, and the overshot body 129 are suflioiently smaller than the internal diameter of the drill stem to provide an annular fluid channel between the aforementioned elements and the drill stem. By providing the aforementioned ports 146, 148 and opening 147, provision is made for selectively bypassing fluid from one side of the resilient collar 153 to the opposide thereof. That is, the intermediate portion of the spindle is of sufficient axial length and the cross bore 148 is located so that when the wire line is retracted as illustrated in FIGURE 4, the coupling element, the spindle, and the elements mounted on the spindle are moved a sufficient distance relative to the jaw element so that the cross bar 148 opens into the annular space enclosed by the adjacent portion of intermediate portion 1413 and the drill stem; and that when the aforementioned members of the valving portion 124 are moved inwardly relative to the main body 123 to a fluid propel position so that the washer 154 abuts against the jaw element, the ports 14% are closed by the inner peripheral wall portion of the annular shoulder 137A. The ports 136, 139 are provided to permit fluid to enter into and exhaust from the opening 138 respective sides of the enlarged portion 141A as the main body and the valving portion are moved between a fluid propel and a retracted position.

Operation After the core of a desired length has been cut, the drilling is stopped and the water swivel is removed from the outer end of the drill stem. Then the drill stem is pulled outwardly a short distance, if it is necessary, to break the core. If appropriate valves have been provided in the drill stern inwardly from the water swivel said valves may be closed to prevent fluid from draining from the drill stem where the drilling direction is upwardly and then the water coupling removed. Now the overshot assembly with a wire line attached thereto is inserted into the drill stern, next the casing head 11% is threaded on the outer end of the drill stem and then appropriate fluid connections are made between the drill stem and the pump 25, and valves are set so that fluid may be forced through the line 24 into the casing head and then into the drill stem. The fluid pressure in the outer end of the drill stern forces the valving portion 124 inwardly relative to the main body 123 until the thrust washer 154 abuts against the jaw element so that the port 143, opens into the annular space between the spindle and the drill stem and thereby prevents fluid to bypass the resilient collar 153. In the event that a fluid seal is not formed between the elements of the overshot assembly and the drill stem, the adjustment nut 151 may be turned in the appropriate direction to expand the resilient collar to form a seal to prevent fluid bypassing the overshot assembly. Now as additional fluid is pumped into the drill stem, the entire overshot assembly with the wire line attached thereto is fluid propelled toward the bit end of the drill stern.

When the overshot assembly has been propelled to contact the core barrel inner tube, the spear point 43 will force the jaws 127 apart so that said jaws will clamp onto the spear point. In the event that the jaws do not clamp onto the spear joint, the wire line may be retracted to pull the overshot assembly a short distance away from the spear in order to utilize a hammering effect of the nature described in U.S. patent application, Ser. No. 761,889.

After the jaws have been clamped over the spear point, the wire line is retracted. The initial retraction of the wire line pulls the valving portion outwardly relative to the main body 123 (from the position illustrated in FIGURE 3 to the position illustrated in FIG- URE 4) and thus opens the fluid channel or fluid flow path designated by arrows 177 to permit fluid to pass through the annular space between the coupling element and the drill stem, next radially inwardly through the ports 146 into the opening 145, then through opening 147 and thence radially outwardly through the cross bore 148 to pass axially through the annular space intermediate the remaining portion of the overshot assembly and the drill stem.

, As may be apparent from the foregoing description, fluid channels are provided to permit the fluid in the drill stem to bypass the overshot assembly and the core barrel inner tube assembly as said assemblies are retracted. Thus the aforementioned assemblies may be retracted at a relatively rapid rate and the fluid is not forced out of the head end of the drill stem. Once the aforementioned assemblies have been retracted to the drill stem casing head end of the drill stem, if a valve is provided inwardly from the inner end of said assemblies, the aforementioned valve may be closed and thus prevent fluid from flowing out of the drill stem once the drill stem casing head is to be removed (provided the drilling direction is in an up wardly direction). After the casing head is removed, the overshot assembly and the core barrel inner tube assembly are removed from the drill stem and an empty core barrel inner tube assembly may be again fluidly propelled to the bit end of the drill stem.

By providing a core barrel inner tube assembly such as that utilizes a centralizer ring and a spacer ring forretaining said assembly in a desired position at the bit end of the drill stem, the inner diameter of the core receiving tube may be of a larger diameter without decreasing the wall thickness of said tube and still use the same inner diameter drill stem than that wherein wire line core barrel equipment having hanger couplings is utilized. Further, the aforementioned rings hold the core barrel inner tube assembly in a centered position in the inner end of the drill stem. 7

As many widely apparently diflerent embodiments of this invention may be made without departing from the spirit and scope thereof, it is to be understood that I do not limit myself to the specific embodiments herein.

What I claim is:

1. A wire line overshot assembly for retracting a core barrel inner tube assembly from the bit end of the drill stem comprising a generally cylindrical main body portion having an outer diameter smaller than the inner diameter of the drill stem to provide an annular space between the main body portion and a drill stem, said main body portion including at one end grapple means for selectively attaching to the core barrel inner tube assembly, and a generally cylindrical coupling portion connected to the opposite end of said main body portion for limited slidable movement inwardly toward and away from the grapple means, said coupling portion including a reduced diameter outer end portion and an enlarged diametri-c cylina coupling portion on the opposite end thereof from the main body portion. y

2. The apparatus of claim 1 further characterized in that the coupling portion includes a'spindle having one end slidable retained in the main body portion and having the fluid channel extending therethrough and that the cylindrical portion is a resilientcollar mounted on said spindle.

' 3. An overshot assembly fluidly propellable to the bit end of a drill stem for clamping onto the core barrel inner tube assembly seated in the bit end of the drill stem to retract 'said core barrel inner tube assembly comprising a main body portion including grappling means mounted in one end of said body portion for selectively clamping onto appropriate shaped end of said core barrel inner tube assembly, a coupling portion having an axially extending fluid channel formed therein, said coupling portion including cylindrical means for substantially forming a fluid fit with the inner peripheral wall of the drill stem, said fluid channel extending through said cylindrical means and opening into the drill stem oneither side of said cylindrical means, said body portion having means 'for connecting the coupling portionfor limited slidable movement inwardly toward and away from the main body portion to alternately block one of the openings when the coupling portion is moved to an inward position relative to the main body portion and unblocking said opening when the coupling portion is moved to an outer position relative to said body portion.

References Cited by the Examiner UNITED STATES PATENTS 2,810,440 10/57 Kenneday; 2,999,545 9/61 Bigelow 166-153 GERALD M. FORLENZA, Primary Examiner.

SAMUEL F. COLEMAN, Examiner. 

1. A WIRE LINE OVERSHOT ASSEMBLY FOR RETRACTING A CORE BARREL INNER TUBE ASSEMBLY FROM THE BIT END OF THE DRILL STEM COMPRISING A GENERALLY CYLINDRICAL MAIN BODY PORTION HAVING AN OUTER DIAMETER SMALLER THAN THE INNER DIAMETER OF THE DRILL STEM TO PROVIDE AN ANNULAR SPACE BETWEEN THE MAIN BODY PORTION AND A DRILL STEM, SAID MAIN BODY PORTION INCLUDING AT ONE END GRAPPLE MEANS FOR SELECTIVELY ATTACHING TO THE CORE BARREL INNER TUBE ASSEMBLY, AND A GENERALLY CYLINDRICAL COUPLING PORTION CONNECTED TO THE OPPOSITE END OF SAID MAIN BODY PORTION FOR LIMITED SLIDALE MOVEMENT INWARDLY TOWARD AND AWAY FROM THE GRAPPLE MEANS, SAID COUPLING PORTION INCLUDINGA REDUCED DIAMETER OUTER END PORTION AND AN ENLARGED DIAMETRIC CYLINDRICAL PORTION, SAID CYLINDRICAL PORTION HAVING A FLUID CHANNEL EXTENDING AXIALLY THERETHROUGH TO OPEN INTO THE HOLLOW PORTION OF THE DRILL STEM ON EITHER SIDE OF SAID CYLINDRICAL PORTION WHEN SAID ASSEMBLY IS POSITIONED IN SAID DRILL STEM, SAID MAIN BODY PORTION INCLUDING MEANS FOR BLOCKING THE FLUID CHANNEL WHEN SAID COUPLING PORTION HAS BEEN MOVED TO AN INNER POSITION RELATIVE TO THE MAIN BODY POORTION AND UNBLOCKING SAID CHANNEL WHEN THE COUPLING PORTION HAS BEEN MOVED OUTWARDLY RELATIVE TO SAID MAIN BODY PORTION, AND WIRE LINE MEANS CONNECTED TO SAID COUPLING PORTION ON THE OPPOSITE END THEREOF FROM THE MAIN BODY PORTION. 